Attempts to induce nocardioform placentitis (Crossiela equi) experimentally in mares

Abstract

We were unable to induce nocardioform placentitis, and there was no evidence of nocardioform microorganisms in endometrial swabs of broodmares before or after mating. These findings suggest that nocardioform placentitis is not induced simply via the presence of nocardiform actinomycetes and that route, insufficient duration of exposure and dose may play a role in the development of disease. Additional predispositions may also be involved in the development of nocardioform placentitis.

Abortursachen beim Pferd – eine Übersicht der Literatur und eigene Auswertungen

“…Eine Infektion des Fetus erfolgt nicht. Die klinische Diagnose vor dem Auftreten des Aborts ist schwierig, da Symptome wie Ausfluss und vorzeitige Euteranbildung meist fehlen(6,14).Die Plazentitis durch eine aszendierende Infektion über die Cervix uteri nimmt den größten Stellenwert im Zusammenhang mit dem equinen Abortgeschehen ein. Sie tritt vor allem bei pluriparen Stuten mit anatomischen Defiziten wie mangelndem Vulvaund Hymenalringschluss oder schlechter Zervixkonformation auf(31).…”

Pathology of equine amnionitis and foetal lLoss: clinical and experimental studies

“…As with EAFL and MRLS, the route of transmission in focal mucoid placentitis cases had not been determined despite experimental attempts to reproduce the lesion using Crossiella spp (Canisso et al, 2014).…”

“…In addition, the exposure of pregnant mares at both of these early stages of pregnancy has for the first time experimentally induced single or multiple focal mucoid lesions on the chorionic surface of the placenta (Cawdell- . Experimental attempts to induce a similar lesion in pregnant mares by intravenous administration, feeding, and direct intracervical inoculation of Crossiella equi have been unsuccessful (Canisso et al, 2014). A number of factors may cause a migrating setal fragment to halt at the foetomaternal junction.…”

“…Experiments undertaken to reproduce the characteristic lesion in pregnant mares by administration per os, intrauterine, intravenous, and intracervical inoculation with Crossiella equi failed to establish an infection leaving the route of transmission a mystery (Canisso et al, 2014). Actinomycete organisms are found extensively in the soil and speculation as to the possibility of inhalation or dermal transmission of these organisms has been discussed (Erol et al, 2012).…”

“…Hairy and urticarial caterpillars which build silken nests occur all over the world including Europe, the Mediterranean, Africa and recently into England (Heppner, 1995;Vega et al, 2011;Veldtman, 2013;Hankey, 2012). Other species of caterpillars and their shed exoskeleton may cause reproductive disease including focal mucoid placentitis in animals similar to the Shedbera caterpillar in North Africa (Volpato et al, 2013;Chapter 2) Confirmation that caterpillar setae migrate from the gut to the foetal membranes after ingestion by the mare in conjunction with the isolation of the same organism in a clinical case of EAFL with focal mucoid placentitis and an induced case of focal mucoid placentitis after gavage with caterpillar exoskeleton, suggests that caterpillar setae cannot be discounted as a vector of transmission for focal mucoid placentitis, especially as attempts to induce the lesion via other traditional routes (transcervical, haematogenous, per os) have been unsuccessful (Canisso et al, 2014). …”